2014-10-01 185 views
0

查詢多個表我有一個Hibernate映射它看起來像這樣:休眠 - 一個休眠映射

<?xml version="1.0" encoding="UTF-8"?> 
<!DOCTYPE hibernate-mapping PUBLIC 
    "-//Hibernate/Hibernate Mapping DTD 3.0//EN" 
    "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"> 

<hibernate-mapping package="org.lwl.anlei.bl.model.imp"> 

    <class name="PersonFo"> 
    <id name="id" type="integer"/>  
    <property name="name" type="string"/> 
    <property name="info" type="string"/> 
    </class> 

    <sql-query name="person1"> 
    <return alias="gb" class="PersonFo"/> 
    SELECT id   as {gb.id}, 
      name  as {gb.name}, 
      info  as {gb.info} 
    FROM table 
    WHERE field1 = :param 
    </sql-query> 

    <sql-query name="person2"> 
    <return alias="gb" class="PersonFo"/> 
    SELECT id   as {gb.id}, 
      second_name as {gb.name}, 
      whatever as {gb.info} 
    FROM table 
    WHERE field2 = :param 
    </sql-query> 

</hibernate-mapping> 

這是什麼,我有simplyfied HBM。 在Java中,我得到我的數據,這樣一來,與「getQueryName」:

List<Person> myPersons = 
    session.getNamedQuery("person1").setString("param", "important text").list(); 

現在,我必須使用視圖,而不是這些querys。我知道,我可以簡單地寫「SELECT XXX FROM view_person1」和「SELECT XXX FROM view_person2」到SQL-querys,但我更願意用這樣的:

<?xml version="1.0" encoding="UTF-8"?> 
<!DOCTYPE hibernate-mapping PUBLIC 
    "-//Hibernate/Hibernate Mapping DTD 3.0//EN" 
    "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"> 

<hibernate-mapping package="org.lwl.anlei.bl.model.imp"> 

    <class name="PersonFo" 
    table="view_person1" 
    entity-name="view_person1" > 
    <id name="id" column="id" type="integer"/>  
    <property name="name" column="name" type="string"/> 
    <property name="info" column="info" type="string"/> 
    </class> 

    <class name="PersonFo" 
    table="view_person2" 
    entity-name="view_person2" > 
    <id name="id" column="id" type="integer"/>  
    <property name="name" column="name" type="string"/> 
    <property name="info" column="info" type="string"/> 
    </class> 

</hibernate-mapping> 

在另一個例子中,我看到了如何通過這種方式通過休眠來保存數據。 Map Two Identical tables (same schema...) to same entity in Hibernate

他們只是使用:

但是,我怎麼查詢數據?是否有這樣的:

List<Person> myPersons = 
    session.getNamedEntity("view_person2").list(); 

幫助將非常appriciated! 謝謝!

回答

1

使用polymorphism="explicit"區分您的命名實體:

<class name="PersonFo" 
    table="view_person1" 
    entity-name="view_person1" polymorphism="explicit" > 
    <id name="id" column="id" type="integer"/>  
    <property name="name" column="name" type="string"/> 
    <property name="info" column="info" type="string"/> 
    </class> 

    <class name="PersonFo" 
    table="view_person2" 
    entity-name="view_person2" > 
    <id name="id" column="id" type="integer"/>  
    <property name="name" column="name" type="string"/> 
    <property name="info" column="info" type="string"/> 
    </class> 

和查詢您的命名實體象下面這樣:

List list1 = session.createQuery("from view_person1").list(); 
List list2 = session.createQuery("from view_person2").list(); 
+0

我會測試。提前致謝! – Stix 2014-10-02 07:21:04